DiploStrat wrote:
-- A volt meter is interesting, but very limited. When on charge, it tells you the voltage of your charge source, not your battery. And the rest of the time, it gives an artificially low reading as most RV's are discharging all the time. Your refrigerator is probably you biggest load.
What you say is why I have a permanently wired ammeter in our RV that constantly monitors the current into (positive ammeter readings) or out of (negative ammeter readings) the coach batteries .... along with a couple of voltmeters that monitor both the voltage on the engine's 12V system from it's alternator and the voltage on the coach's 12V system.
The voltage on the coach'es 12V system can represent that from the batteries only, or represent that from the engine alternator, or represent that from the converter powered by the generator, or represent that from the converter powered by hookups.
No matter what the source, whenever the coach's 12V system voltmeter indicates that voltages greater than about 12.8 volts are present and the ammeter indicates coach battery current is zero or only slightly positive ... then the coach batteries are fully charged. This is a very simple and full-proof battery condition monitoring method that has worked well for us for years on AGM coach batteries.
